.300 HOME LOADING
There is some truth in what they say, but only if their reloading technique is flawed; in which case any rimmed or belted case will be overworked in the reloading process and will have its useful life reduced.
The .300 H&H was launched in 1925 – the same year as the .270 Winchester – with the thunderous title, “.300 Belted Rimless Magnum Nitro Express.”
It was and still is a wonderful cartridge and with proper reloading the brass cases should last for many reloads.
There are more modern, more efficient cartridges available nowadays but none can compete with the pure pleasure of using a historic cartridge in an equally historic rifle.
There’s more to life than mere efficiency.
Factory ammo headspaces on the belt and if you full-length resize every time, the brass case will have to stretch on firing to fit the chamber again.
Repeated working hardens the brass which then splits.
The best way to reduce this overworking is to back off the sizing die until it only sizes about a calibre length of the neck.
This allows a good grip on the bullet but leaves the shoulder – such as it is in the .300 H&H – untouched so that it can give some support to the case when next it is fired.
After sizing, always check the case length, trim back to just under 2.850in if necessary, and then re-chamber the neck to remove any burrs.
That way, your cases should last for many reloads.